﻿public class MusicTitles
{
    private string[] _names = {
              "Tubular Bells", "Hergest Ridge",
              "Ommadawn", "Platinum" };

    public IEnumerator<string> GetEnumerator()
    {
        for (int i = 0; i < 4; i++)
        {
            yield return _names[i];
        }
    }

    public IEnumerable<string> Reverse()
    {
        for (int i = 3; i >= 0; i--)
        {
            yield return _names[i];
        }
    }

    public IEnumerable<string> Subset(int index, int length)
    {
        for (int i = index; i < index + length; i++)
        {
            yield return _names[i];
        }
    }
}
